Impact of third ventricle invasion pattern by large craniopharyngiomas on the outcome of surgical tumor resection

Abstract

Objective To assess the impact of the positional relationship between the large craniopharyngiomas and the third ventricle on the outcome of surgical resection of the tumors. Methods In 72 cases of craniopharyngiomas, the tumors were classified into two types according to the radiographic and surgical findings defining the relationship between the tumors and the third ventricle. For each type of tumors, 3 grades were classified based on the tumor size, texture, and infiltration pattern of the third ventricle. The extend of tumor removal was confirmed by both intraoperative evaluation and postoperative CT or magnetic resonance imaging. The correlation between the degree of hypothalamus invasion and the extend of tumor removal was analyzed in all the cases. Results The craniopharyngiomas were classified into two types, namely those residing in the third ventricle (7 cases) and those invading the third ventricle(65 cases). The degree of tumor resection was significantly different between the 3 grades: total tumor removal was achieved in 95.7% of grade Ⅰ cases, in 80.0% of grade Ⅱ cases, and in only 47.4% of grade Ⅲ I cases (P<0.05). conclusion Understanding of the anatomical relationship of the tumor to the third ventricular floor can be great value for improving the outcome of surgical resection of large craniopharyngiomas. Key words: Craniopharyngiomas; Hypothalamus; Third ventricle; Surgical outcomes